Topical chemotherapeutic treatment of mucous membranes or other moist areas of the human body is problematic because of the inherent challenge of maintaining the localization of the pharmaceutical at the point of contact. In the mouth area, for example, in the cheeks, gums, tongue, or pallet area, as well as the lips, it is difficult to maintain a presence of a topically applied pharmaceutical because of its tendency to wash away with the patient's saliva and movements of the mouth which are normally present. While various bioadhesive formulations have been proposed for application to such moist areas, they have not been completely successful and there exists the need for additional bioadhesive pharmaceutical carrier materials for application to mucous membrane and other moist body areas.
For example, Gallopo et al. in U.S. Pat. No. 4,915,948 have developed a tablets for bioadhesion to mucous membranes. The tablets comprise effective amounts of a water soluble biopolymer selected from the group consisting of a xanthan gum, a pectin, and mixtures thereof and a solid polyol. The polyol may be a sugar alcohol such as sorbitol or xylitol. Various pharmaceutical additives can be provided in such a tablet to provide for a controlled release of such pharmaceutical actives. It is the object of the present invention to provide a more convenient bioadhesive pharmaceutical carrier that can be applied to mucous membrane and other moist body areas which is in a gel form that not only provides good bioadhesion but also control release of pharmaceuticals therefrom.